Log debarking apparatus

ABSTRACT

A curving arm member and mounting assembly for use with a ring type log debarker. The mounting assembly comprises a shaft and cantilevered mounting plate to which the arm member is attached in a plane perpendicular to the axis of the shaft. The arm member has front and rear faces reducing in width from base to tip and leading and trailing edges at opposite sides thereof. A bark cutting edge is provided at the tip. The front face and leading edge converge in a spiral-like log engaging climbing edge from the base to the top. The cutting edge and a substantial portion of the climbing edge are carried on a removable insert member.

United States Patent 1 Bowers 1 Jan. 9, 1973 [54] LOG DEBARKING APPARATUS [76] Inventor: Richard W. Bowers, PO. Box 13, Waldo, Ark. 71770 [22] Filed: July 8, 1971 21 Appl. No.: 160,788

[52] U.S. Cl. ..l44/208 E, 144/218, 144/241 [51] Int. Cl. ..B27l1/00 [58] Field of Search....144/208 E, 208, 218, 2 Z, 241

[56] References Cited UNITED STATES PATENTS 2,787,304 4/1957 Brundell et al ..l44/208 E 2,903,028 9/1959 Brundell et al..... ....l44/208 E 2,911,020 11/1959 Wennberg ..l44/208 E Primary Examiner-Donald R. Schran Attorney-Carlos A. Torres et a1.

[57] ABSTRACT A curving arm member and mounting assembly for use with a ring type log debarker. The mounting assembly comprises a shaft and cantilevered mounting plate to which the arm member is attached in a plane perpendicular to the axis of the shaft. The arm member has front and rear faces reducing in width from base to tip and leading and trailing edges at 0pposite sides thereof. A bark cutting edge is provided at the tip. The front face and leading edge converge in a spiral-like log engaging climbing edge from the base to the top. The cutting edge and a substantial portion of the climbing edge are carried on a removable insert member.

10 Claims, 5 Drawing Figures PATENTEDJAH 9:913

Richard. W Bowers FIG. 2 INVENTOR BY Can! ,4. 72

FIG.4

ATTORNEYS LOG DEBARKING APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to log debarkers. In particular, it concerns the tools and arms for carrying such tools for use with a ring type log debarker.

2. Brief Description of the Prior Art In one of the most popular types of log debarkers, a plurality of arm members, on the ends of which are carried bark cutting tools, are mounted for rotation on a ring or drum member, through which a passage is provided. Logs are fed axially through the passage while the rotating debarking tools scrape the bark from the log. The tool carrying arms are usually curved, like a sickle blade, and mounted in such a manner as to form a spiral pattern, the center of which lies generally on the axis of the passage through the ring. These arms are generally spring biased, in some manner, so as to engage the log with enough force to scrape the bark therefrom. The following patents are cited to show the state of ring type debarker art:

2,880,771 Annis, Jr. 2,983,291 Dick 3,026,91 9 Lunn 3,128,806 Shields 3,173,329 Smith 3,189,067 Dillingham 3,236,273 Rich, et al.

In addition to the tool or cutting edge, the arms of some of these debarkers are provided with a climbing edge engageable with the end of a log for opening the arms. As the end of a log is slammed into these climbing edges, spiral grooves are formed and, as the arms continue to rotate, these climbing edges cause the arms to move radially outward along the grooves until they are opened enough to allow passage of the log and engagement of the tool cutting edge with its bark. For a clearer understanding of such a climbing edge, reference may be made to the aforementioned U.S. Pat. No. 2,880,771.

Naturally the cutting edge of the debarking tool is dulled after prolonged use and requires sharpening. In an effort to reduce downtime, replaceable inserts have been developed on which the cutting edge is carried. Thus a dulled cutting edge insert may be replaced by a new one in a short period of time. However, the climbing edges on the tool carrying arms also frequently become dulled, rendering the arms incapable of selfopening. In the past this has required either time consuming sharpening or replacement of the entire arm member. Furthermore, the mounting of many types of ring debarker arms leaves something to be desired. The great force usually applied to such a mounting occasionally results in a broken arm or a sloppy connection which may eventually damage the arm beyond quick repair.

SUMMARY OF THE INVENTION In the present invention a tool carrying arm is provided which eliminates many of the problems inherent in other designs. An insert is provided which not only permits replacement of the debarking cutting edges, but also permits replacement of a substantial portion of following description and observation of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a perspective view of a debarking arm and associated mounting assembly according to a preferred embodiment of the invention, for use with a ring type debarker;

FIG. 2 ,is an elevation view of the front face of a debarking arm, according to a preferred embodiment of the invention;

FIG. 3 is an elevation view of the leading edge of the debarking arm of FIG, 2 taken along lines 3-3 thereof;

FIG. 4 is an-elevatio n view of the debarking arm of FIG. 2 as viewed from the trailing edge, taken along line 4-4 of FIG. 2; and

FIG. 5 is an elevation view of the cutting end of the debarker arm of FIG. 2, as viewed from the rear face thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, there is shown a debarking arm or blade 10 to be used with a ring type debarker. The base of the arm is provided with a plurality of holes 11 by which the arm may be attached to a mounting plate 21 by a plurality of studs 22. The arrangement of holes 11 and studs is important. By placing the outer two studs at a point below the longitudinal center line of plate 21, a greater surface is provided against which the base of arm 10 may bear when subjected to a concentrated force at its tip in a direction parallel to the axis of shaft 20 and toward the splined area 25, as it would be when a log is fed through the debarker.

The mounting plate 21 is attached near one end to the end of shaft 20. Shaft 20 maybe provided with a splined end 25 for attachment to a torsion spring device (not shown) on the rotating portion of a ring debarker. Of course, there would be a plurality of arms and associated shafts 20 affixed at regularintervals-about the rotating portion. The torsion spring devices would bias the tips-of the arms 10 toward the center of a passage through which logs would be axially fed for debarking. This arrangement is familiar to those skilled in the art and is shown in the aforementioned patents.

Referring now to FIGS. 2 through 5, a detailed description of the debarking arms 10 will be given. As previously mentioned the base of each arm is provided with a plurality of mounting holes 11. The arm is curved and decreases in width toward its tip where a cutting or scraping edge 31 is provided. Sloping away from the front face 15 and the leading edge of the arm are mutually converging surfaces 32 and 33 which terminate in a sharp spiral curved climbing edge 34. As previously described, the climbing edge 34 is the first portion of blade 10 to engage the end of a log causing the blades to be self-opened and allowing the debarking edge 31 to engage the periphery of the log.

The cutting edge 31 and a substantial portion 340 of climbing edge 34 lies on an insert member 50 carried by the arm 10. The insert 50 is affixed to a mounting bracket 55 which is welded to the rear face 39 of arm 10, in a curving plane substantially perpendicular thereto, by a pair of countersunk bolts 51 with selflocking nuts 53. Mounting bracket 55 lies along the back of the curved insert 50 and projects further toward the base of arm in a tapered reinforcing portion 55a to add additional strength to the tip end of arm 10.

Thus, a debarking arm is provided with a replaceable insert which not only supplies a new cutting edge, but also supplies a substantially new climbing edge. Only on rare occasions will the entire arm be replaced, since it is the tip portion of the climbing edge which receives the most wear. By unloosening two nuts these inserts may be replaced in a matter of minutes. Prior designs which require replacement of the entire arm result in a downtime of several hours. Furthermore, the present invention provides an arm which is less likely to break or become sloppy in its mounting. The combination of all of these improvements results in a debarking arm which is unsurpassed in overall performance.

Although only one embodiment of the invention has been described herein, many variations will become apparent to those skilled in the art. Therefore, it is intended that the scope of the invention be limited only by the claims which follow.

I claim:

1. For use in a ring type debarker, a curving arm member having front and rear faces reducing in width from the base of said a'rm member to its tip and having a leading edge and a trailing edge at the opposite sides of said faces, the tip end of said arm being provided with a cutting edge, the front face and leading edge of said arm converging in a log engaging climbing edge ex tending from the base of said arm to its tip, said cutting edge and substantial portion of said climbing edge being carried on insert means removable from the remainder of said arm.

2. A debarking arm as set forth in claim 1, characterized in that said insert means is attached to a bracket member affixed to the rear face of said arm member, said bracket member lying along the back of said insert means and extending therefrom toward said base for reinforcement of said tip.

3. A debarking arm as set forth in claim 1, in combination with a mounting shaft for connection to the 4 rotatable portion of a ring type debarker, said arm being attached to the end of said shaft by an elongated cantilevered mounting plate in a plane substantially perpendicular to the axis of said shaft.

4. A debarking arm as set forth in claim 3, characterized in that said arm is attached to said mounting plate by a plurality of bolt means whose axes are parallel to the axis of said shaft, at least two of said bolt means being below the longitudinal centerline of said elongated mounting plate.

5. A debarking arm as set forth in claim 1, characterized in that said front face and said leading edge comprise mutually sloping surfaces which converge in said climbing edge along a spiral-like curve.

6. For use in a ring type debarker, a curving arm member having front and rear faces reducing in width from a base to a tip and having leading and trailing edges at the opposite sides of said faces, the tip of said arm being provided with a cutting edge substantially perpendicular to said front and rear faces, the front face and leading edge of said arm having mutually sloped surfaces converging in a spiral curved log engaging climbing edge extending from said base to said tip, said cutting edge and a substantial portion of said climbing edge being carried on an insert portion of said arm for removal and replacement.

' 7. An armmember as set forth in claim 6, in combination with shaft means for mounting said arm member on the rotating portion of a ring type debarker, said shaft means comprising an elongated plate member attached to one end of a shaft in a plane perpendicular to the axis of said shaft, said arm member being connected to said plate in a plane parallel thereto by a plurality of bolt members, the axes of which are parallel to said shaft axis.

8. An arm member as set forth in claim 7, characterized in that the axes of at least two of said bolt members lie below the centerline of said plate member. I

9. An arm member as set forth in claim 6, characterized in that said insert portion comprises a curved plate the'back of which lies against a mounting bracket to which it is fastened.

10. An arm member as set forth in claim 9 characterized in that said mounting bracket is affixed to the rear face of said arm member and projects a substantial distance from the said back of said insert portion toward the base of said arm memberfor reinforcement thereof. 

1. For use in a ring type debarker, a curving arm member having front and rear faces reducing in width from the base of said arm member to its tip and having a leading edge and a trailing edge at the opposite sides of said faces, the tip end of said arm being provided with a cutting edge, the front face and leading edge of said arm converging in a log engaging climbing edge extending from the base of said arm to its tip, said cutting edge and substantial portion of said climbing edge being carried on insert means removable from the remainder of said arm.
 2. A debarking arm as set forth in claim 1, characterized in that said insert means is attached to a bracket member affixed to the rear face of said arm member, said bracket member lying along the back of said insert means and extending therefrom toward said base for reinforcement of said tip.
 3. A debarking arm as set forth in claim 1, in combination with a mounting shaft for connection to the rotatable portion of a ring type debarker, said arm being attached to the end of said shaft by an elongated cantilevered mounting plate in a plane substantially perpendicular to the axis of said shaft.
 4. A debarking arm as set forth in claim 3, characterized in that said arm is attached to said mounting plate by a plurality of bolt means whose axes are parallel to the axis of said shaft, at least two of said bolt means being below the longitudinal centerline of said elongated mounting plate.
 5. A debarking arm as set forth in claim 1, characterized in that said front face and said leading edge comprise mutually sloping surfaces which converge in said climbing edge along a spiral-like curve.
 6. For use in a ring type debarker, a curving arm member having front and rear faces reducing in width from a base to a tip and having leading and trailing edges at the opposite sides of said faces, the tip of said arm being provided with a cutting edge substantially perpendicular to said front and rear faces, the front face and leading edge of said arm having mutually sloped surfaces converging in a spiral curved log engaging climbing edge extending from said base to said tip, said cutting edge and a substantial portion of said climbing edge being carried on an insert portion of said arm for removal and replacement.
 7. An arm member as set forth in claim 6, in combination with shaft means for mounting said arm member on the rotating portion of a ring type debarker, said shaft means comprising an elongated plate member attached to one end of a shaft in a plane perpendicular to the axis of said shaft, said arm member being connected to said plate in a plane parallel thereto by a plurality of bolt members, the axes of which are parallel to said shaft axis.
 8. An arm member as set forth in claim 7, characterized in that the axes of at least two of said bolt members lie below the centerline of said plate member.
 9. An arm member as set forth in claim 6, characterized in that said insert portion comprises a curved plate the back of which lies against a mounting bracket to which it is fastened.
 10. An arm member as set forth in claim 9 characterized in that said mounting bracket is affixed to the rear face of said arm member and projects a substantial distance from the said back of said insert portion toward the base of said arm member for reinforcement thereof. 